How do I Replace the Low Beam Plugs on a 1997 Lexus SC 400?
- 1). Raise the hood of the SC400 and set the hood prop, to support the hood for the duration of this project. Visually inspect and locate the mounting tabs on top of each headlight assembly. Remove the two mounting bolts from the top of each headlight assembly, using a 3/8-inch drive ratchet and socket. Turn the bolts counterclockwise until you can remove them by hand.
- 2). Pull the driver's side headlight out of the front bumper area toward you, and disconnect the low beam headlight and socket from the rear of the assembly. Repeat this process on the passenger side. Push the light bulbs, sockets and wiring for the low beam lights, back through the front headlight area, so you can access the entire assembly and wiring from behind the radiator support. Set the headlight assemblies back into their respective places temporarily, so that they do not hang loose during the rest of this project.
- 3). Cut one of the old headlight wiring sets about 1 to 2-inches behind the old light socket, and remove the old headlight socket completely from the car. Leave yourself plenty of slack in the wiring for installation of the new socket. Use a multipurpose wiring hand tool to cut the old socket wires.
- 4). Unsheathe or remove the plastic covering from about 1/4-inch of both old wires at the socket end, using the multipurpose tool. This will expose clean wire to connect the old and new wires together. Place the black wire from the new socket into a butt-end electrical connector, and crimp the connector with the multipurpose electrical tool. Place the existing or old black wire into the opposite end of the connector, and crimp the connector. This will join your negative wires together between the car and new headlight socket.
- 5). Place the colored wire from the new light socket into a butt-end electrical connector, and crimp the connector onto the wire with a multipurpose electrical hand tool. Install the colored wire from the existing car wire into the opposite end of the connector. Crimp the second end of the connector with the multipurpose tool. This will connect your positive wire on the new socket to the existing wire on the car.
- 6). Put on a pair of rubber gloves or cloth work gloves. Install one new low beam light bulb into the new light socket. Set the light and socket down, in order to go to the driver's side of the car and turn on the headlights. Check to ensure that the new headlamp is working before reinstalling it in the headlight assembly. If your new headlamp is not working, double check your wiring. If your wiring is good, then you may have a short in the entire light system.
- 7). Install the light bulb through the hole in the radiator support, and forward to the bumper area. Install the new bulb and socket into the headlight assembly. Reinstall the headlight assembly and tighten the mounting bolts. Use a 3/8-inch drive ratchet and socket to snug the mounting bolts for the headlight assembly. You do not need to torque these bolts, and doing so will break the headlight mounting tabs.
- 8). Repeat Steps 3 through 7 to complete the replacement of the second low beam headlight socket. All removal, installation, and testing procedures are identical for the second side of the vehicle.
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